Passage
In that day you will know that I am in my Father, and you in me, and I in you.
John 14:20 (WEB)
Nearby Context
John 14:18 I will not leave you orphans. I will come to you.
John 14:19 Yet a little while, and the world will see me no more; but you will see me. Because I live, you will live also.
John 14:20 In that day you will know that I am in my Father, and you in me, and I in you.
John 14:21 One who has my commandments, and keeps them, that person is one who loves me. One who loves me will be loved by my Father, and I will love him, and will reveal myself to him.”
John 14:22 Judas (not Iscariot) said to him, “Lord, what has happened that you are about to reveal yourself to us, and not to the world?”
Study Lenses
The verse centers on "father". It is saying that the verse draws attention to "father" and "the identity of Jesus", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 19's "Yet a little while and the world..." into verse 21's "One who has my commandments and keeps...", so "father" and "the identity of Jesus" belong inside that flow. In John context, the local focus is the identity of Jesus, new birth, eternal life, and belief and unbelief.
A plain takeaway is to answer the verse's own emphasis on "father" with trust shaped by these words, not by a vague optimism outside the passage.